Soyoung Lee

On-chip Escherichia coli culture, purification, and detection of expressed proteins

In a recent study, we reported the results of a rapid high-throughput expression analysis of the affinity-tagged proteins present in total cell lysates, using a surface plasmon resonance (SPR) imaging protein chip system. In this paper, we describe a novel method, which is able to sequentially carry out a recombinant Escherichia coli culture, as well as the detection and purification of the expressed proteins on a single microwell chip, fabricated on a two-dimensional thin gold film. Following the induction of the protein on the microwell chip, the E. coli cells were lysed on the chip via the addition of lysozymes, and the expressed glutathione S-transferase-fused green fluorescent protein (GST–GFP) was then purified on the chip via affinity interaction with the glutathionylated gold surface of the chip. Finally, the expressed protein was directly detected using the surface plasmon resonance (SPR) imaging system. This system saves a substantial amount of time, experimental resources, and labor, by allowing for the complicated and labor-intensive procedures inherent to the production of recombinant proteins to be conducted on a single microwell chip, simply and economically.

Sesquiterpenoids from the Rhizomes of Curcuma phaeocaulis and Their Inhibitory Effects on LPS-Induced TLR4 Activation.

Two new guaiane-type (2, 6) and one new furanogermacrane-type (11) sesquiterpenoids have been isolated along with twelve known compounds from an EtOAc-soluble extract of Curcuma phaeocaulis rhizomes. The structures of the isolated compounds were elucidated using a combination of NMR, MS, and circular dichroism (CD) spectra. The inhibitory effects of each compound on lipopolysaccharide (LPS)-induced Toll-like receptor 4 (TLR4) activation in THP-1-Blue cells were assessed, and compound 4 showed more potent inhibitory activity against LPS-stimulated TLR4 activation.

Lactococcus lactis KR-050L extract suppresses house dust mite induced-atopic skin inflammation through inhibition of keratinocyte and mast cell activation

Atopic dermatitis (AD) is a chronic inflammatory skin disease, with a steadily increasing prevalence. Lactic acid bacteria (LAB) have been widely used in the food industry and are an attractive option for preventing and treating allergic skin diseases. We previously isolated new LABs including Lactococcus lactis KR‐050L from Gajuknamu kimchi, and showed the anti‐inflammatory effects of extract of L. lactis KR‐050L culture broth (LLK). In this study, we investigated the effects of LLK on AD.

Inhibitory Effects of Compounds and Extracts from Ampelopsis brevipedunculata on IL-6-Induced STAT3 Activation

Ampelopsis brevipedunculata (Maxim.) Trautv. (AB), a traditional East Asian medicine, exhibits protective effects against several inflammatory diseases. Our search for an inhibitor of IL-6-induced JAK2/STAT3 activation revealed that AB ethanolic extract (ABE) had a significant inhibitory effect on IL-6-induced STAT3 expression in Hep3B cells. The isolation and purification of an EtOAc-soluble fraction of ABE (ABEA) using reversed-phase high-performance liquid chromatography (RP-HPLC) afforded 17 compounds. The structures of these compounds (1-17) were elucidated based on 1H and 13C nuclear magnetic resonance (NMR) spectroscopy as well as electrospray-ionization mass spectrometry (ESI-MS) data. ABE and ABEA were screened by a luciferase assay using Hep3B cells transfected with the STAT3 reporter gene. ABEA exhibited potent inhibitory effects on IL-6-induced STAT3 expression; moreover, these effects arose from the inhibition of the phosphorylation of the STAT3, JAK2, and ERK proteins in U266 cells. In addition, the compounds isolated from ABEA were measured for their inhibitory effects on IL-6-stimulated STAT3 expression. Of the compounds isolated, betulin showed the greatest inhibitory effects on IL-6-induced STAT3 activation in the luciferase assay (IC50 value: 3.12 μM). Because of its potential for inhibiting STAT3 activation, A. brevipedunculata could be considered a source of compounds of pharmaceutical interest.

Anti-inflammatory effects of ursolic acid-3-acetate on human synovial fibroblasts and a murine model of rheumatoid arthritis

&NA; Ursolic acid (UA), a pentacyclic triterpenoid, is a common natural substance known to be effective in the treatment of inflammation, oxidative stress, and ulcers in arthritis. This study examined the effects of ursolic acid‐3‐acetate (UAA), a derivative of UA, on rheumatoid arthritis (RA) and verified the underlying mechanism of action by using a type‐II collagen‐induced arthritis (CIA) mice model and tumor necrosis factor (TNF)‐&agr;‐stimulated RA synovial fibroblasts. The oral administration of UAA showed a decrease in clinical arthritis symptoms, paw thickness, histologic and radiologic changes, and serum IgG1 and IgG2a levels. UAA administration reduced Th1/Th17 phenotype CD4+ T lymphocyte expansion and inflammatory cytokine production in draining lymph nodes. In addition, UAA effectively reduced the expression and production of inflammatory mediators, including cytokines and matrix metalloproteinase‐1/3 in the knee joint tissue and RA synovial fibroblasts, through the downregulation of IKK&agr;/&bgr;, I&kgr;B&agr;, and nuclear factor‐&kgr;B. Our findings showed that UAA modulated helper T cell immune responses and matrix‐degrading enzymes. The effects of UAA were comparable with those of the positive control drug, dexamethasone. In summary, all the evidence presented in this paper suggest that UAA could be a therapeutic candidate for the treatment of RA. HighlightsUrsolic acid‐3‐acetate (UAA) attenuated chronic rheumatoid arthritis (RA) symptoms.UAA is more effective than ursolic acid, the known drug candidate for RA.UAA might be a potential candidate for the treatment of arthritic diseases.